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Kinetics of Ordering in Fe3Al: Experiment

Published online by Cambridge University Press:  28 February 2011

Brent Fultz
Affiliation:
California Institute of Technology, Dept. of Materials Science 138-78, Pasadena, California, USA
Zheng-Qiang Gao
Affiliation:
California Institute of Technology, Dept. of Materials Science 138-78, Pasadena, California, USA
Lawrence Anthony
Affiliation:
California Institute of Technology, Dept. of Materials Science 138-78, Pasadena, California, USA
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Abstract

Alloys near the Fe3Al stoichiometry were prepared far from thermodynamic equilibrium by rapid solidification methods. These highly disordered materials were then annealed at low temperatures to develop B2 and D03 order. Both shortrange and long-range order (SRO and LRO) were measured by Mössbauer spectrometry and by x-ray diffractometry, respectively. The SRO was found to evolve in two stages: an initial quick growth of the SRO alone, followed by a slower growth of SRO along with LRO. As expected, at lower temperatures the absolute rates of growth of order were suppressed, but more interestingly, the relative rates of growth of B2 and D03 long-range order parameters were different at different temperatures of annealing. When the B2 order parameter is graphed against the D03 order parameter, at lower temperatures the “kinetic path” through this graph shows that B2 order evolves relatively more rapidly than D03 order.

Type
Research Article
Copyright
Copyright © Materials Research Society 1991

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